U.S. patent number 4,638,526 [Application Number 06/713,031] was granted by the patent office on 1987-01-27 for nozzle assembly for vacuum cleaner.
This patent grant is currently assigned to Matsushita Electric Industrial Co., Ltd.. Invention is credited to Tsuyoshi Hatano, Yoshitaka Murata, Hideo Ohkubo.
United States Patent |
4,638,526 |
Murata , et al. |
January 27, 1987 |
Nozzle assembly for vacuum cleaner
Abstract
A suction nozzle assembly for a vacuum cleaner, which has a
suction spout having a coupling stem for fluid-connection with the
vacuum cleaner, a generally rectangular nozzle housing tiltably
connected with the suction spout and having a sweeping surface
defined at the bottom thereof and adapted to confront a surface to
be cleaned, an elongated brush assembly carried by the nozzle
housing for movement between projected and retracted positions in a
direction perpendicular to the longitudinal sense of the housing
through the sweeping surface, a brush height adjustment device for
adjustably moving the brush assembly to any one of the projected
and retracted positions, and a restraint device for restraining the
housing from undergoing an arbitrary tilting motion relative to the
suction spout.
Inventors: |
Murata; Yoshitaka (Shiga,
JP), Hatano; Tsuyoshi (Yokaichi, JP),
Ohkubo; Hideo (Yokaichi, JP) |
Assignee: |
Matsushita Electric Industrial Co.,
Ltd. (Kadoma, JP)
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Family
ID: |
26393106 |
Appl.
No.: |
06/713,031 |
Filed: |
March 18, 1985 |
Foreign Application Priority Data
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Mar 19, 1984 [JP] |
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59-52507 |
Mar 19, 1984 [JP] |
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59-52548 |
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Current U.S.
Class: |
15/367; 15/373;
15/398; 15/415.1 |
Current CPC
Class: |
A47L
9/06 (20130101); A47L 9/0673 (20130101); A47L
9/0653 (20130101) |
Current International
Class: |
A47L
9/06 (20060101); A47L 009/06 () |
Field of
Search: |
;15/365,367,368,373,371,393,396,397,390,399,400,402,415 R-422/
;15/354,361 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1340535 |
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Sep 1963 |
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FR |
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6800789 |
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Jul 1969 |
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NL |
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Primary Examiner: Moore; Chris K.
Attorney, Agent or Firm: Wenderoth, Lind & Ponack
Claims
What is claimed is:
1. A suction nozzle assembly for a vacuum cleaner, which comprises:
a suction spout having a coupling stem for fluid-connection with
the vacuum cleaner, a generally rectangular nozzle housing tiltably
connected with the suction spout and having a sweeping surface
defined at the bottom thereof, said sweeping surface being adapted
to confront a surface to be cleaned, an elongated brush assembly
carried by the nozzle housing for movement between projected and
retracted positions in a direction perpendicular to the
longitudinal direction of the housing through the sweeping surface,
a brush height adjustment means for adjustably moving the brush
assembly to either the projected or the retracted position, and a
restraining means for restraining the housing from undergoing an
arbitrary tilting motion relative to the suction spout, said
restraining means being operatively associated with said brush
height adjustment means.
2. An assembly as claimed in claim 1, wherein said suction spout
also has a generally cylindrical barrel lying at right angles to
the connecting stem, but in parallel to the longitudinal direction
of the housing, and wherein said restraining means comprises an
engagement piece on the brush height adjustment, said engagement
piece being engageable in a recess defined in one end of the
cylindrical barrel to prevent the housing from undergoing the
arbitrary tilting motion relative to the connecting spout.
3. An assembly as claimed in claim 2, wherein said recess is of a
generally V-shaped configuration.
4. An assembly as claimed in claim 1, wherein said suction spout
also has a generally cylindrical barrel lying at right angles to
the connecting stem, but in parallel to the longitudinal direction
of the housing, and wherein said restraining means comprises a
brake shoe provided on the brush height adjustment for sliding
engagement with one end of the transverse barrel.
5. An assembly as claimed in claim 1, wherein said suction spout
also has a generally cylindrical barrel lying at right angles to
the connecting stem, but in parallel to the longitudinal direction
of the housing, and wherein said restraining means comprises an
engagement pin member supported by the brush height adjustment and
urged in one direction for engagement in a hole defined in one end
of the transverse barrel, said pin member when engaged in said hole
restraining the housing from undergoing the arbitrary tilting
motion relative to the connecting spout.
6. An assembly as claimed in claim 1, wherein said height
adjustment means comprises means for moving the brush assembly in a
plurality of steps between the projected and retracted
positions.
7. An assembly as claimed in claim 6, wherein the brush height
adjustment means is movable in a direction parallel to the
longitudinal direction of the housing and comprises a frame and an
elastic tongue having one end formed integrally with said frame and
extending lengthwise of the housing, the other end of said tongue
having a detent piece thereon, and a plurality of detent recesses
in a portion of the housing confronting the path of movement of the
detent piece for selective engagement with the detent piece.
8. An assembly as claimed in claim 7, further comprising a
generally arcuate leaf spring provided in a region corresponding to
the positions of the detent recesses other than the detent recesses
positioned on the opposite extremities of the path of movement of
the detent piece.
9. An assembly as claimed in claim 6, wherein the brush height
adjustment means is movable in a direction parallel to the
longitudinal direction of the housing, and comprises a frame and
first and second elastic tongues with one end integral with said
frame and extending lengthwise of the housing, the other end of
each of said elastic tongues having a detent piece thereon, and
wherein a portion of the housing along the path of movement of the
detent piece on the first tongue having a plurality of first detent
recesses therein for selective engagement with the detent piece on
the first tongue, and further comprising a cam member on the
interior of the housing in alignment with the path of movement of
the detent piece on the second tongue, said cam member having at
least one second detent recess therein for selective engagement
with the detent piece on the second tongue, the number of said
second recesses being two less than that the member of first detent
recesses, said second detent recesses being paired with the first
detent recesses other than the two first detent recesses which are
positioned on the opposite extremities of the path of movement of
the tongues.
10. An assembly as claimed in claim 6, wherein the means for moving
the brush assembly comprises stepped guide grooves each having a
plurality of steps at different elevations, and a plurality of pins
on said brush assembly equal in number to the number of the stepped
guide grooves and movably engaged in the respective stepped guide
grooves.
11. A suction nozzle assembly for a vacuum cleaner, which
comprises: a generally rectangular nozzle housing having a suction
channel defined at the bottom thereof, a lip member made of
flexible material and depending from the housing on one side of,
and generally in parallel to, the suction channel, a pair of
brushes extending downwardly from the housing on the opposite side
of the lip member from the suction channel and on the other side of
the suction channel from the lip member, respectively, for movement
between projected and retracted positions through an intermediate
position, and a brush height adjustment means carried by the
housing for movement in a direction lengthwise of the housing for
movement between maximum and minimum projected positions through an
intermediate height position, said brushes when said brush height
adjustment means is moved to the minimum projected position being
held in the retracted position at which the distance the brushes
extend downwardly from the bottom of the housing is less than the
distance the lip members depends, said brushes when said brush
height adjustment means is moved to the intermediate projected
position being held in the intermediate position at which the
distance the brushes extend downwardly from the bottom of the
housing is generally equal to the distance the lip member depends,
and said brushes when said brush height adjustment means is moved
to the maximum projected position being held at the position at
which the distance the brushes extend downwardly from the bottom of
the housing is greater than the distance the lip member depends.
Description
BACKGROUND OF THE INVENTION
The present invention relates to a suction nozzle assembly for a
household vacuum cleaner.
There is known a generally T-shaped nozzle assembly for a household
vacuum cleaner which comprises a generally rectangular flattened
box-like housing, occupying the position of a transverse bar of the
shape of a figure "T", and a suction spout occupying the position
of a vertical bar of the shape of the figure "T". The housing has a
suction channel defined at the bottom thereof so as to extend over
the length thereof and is adapted to be moved over the surface to
be cleaned with the suction channel opening towards such surface.
The spout is used to communicate the suction channel to a source of
vacuum which may be either a wheeled canister or a vacuum valve and
is of a generally T-shaped construction including a transverse
barrel and a coupling stem protruding perpendicularly from an
intermediate portion of the transverse barrel for fluid-connection
with the vacuum source.
The transverse barrel is so journalled at its opposite ends to the
housing so as to permit the housing to be tiltable about the
longitudinal axis thereof relative to the coupling stem. The
suction channel at the bottom of the housing is channeled to the
vacuum source through the transverse barrel, then through the
suction spout, and finally through an extension tubing including,
for example, a wand or tubular handle connected to the coupling
stem.
The nozzle assembly also comprises a pair of elongated brushes
built therein so as to extend generally parallel to, and on
respective sides of, the suction channel, which brushes are so
adjustably carried by the housing that the spacing between the
bottom of the housing and the surface to be cleaned can be adjusted
to apply an efficient cleaning action to the surface to be cleaned.
In general, the paired brushes are permitted to protrude to a
smaller brush height when a carpet is desired to be cleaned, and to
a greater brush height when a floor is desired to be cleaned.
The nozzle assembly of the above described construction is
convenient in that, since the housing and the spout are relatively
tiltably connected together, the plane of opening of the suction
channel can be kept substantially parallel to the surface to be
cleaned even though the angle of inclination of the tubular handle
changes relative to such surface during repeated forward and
backward movement of the nozzle assembly and/or as a result of
changes in posture of the operator running the vacuum cleaner.
However, when in the course of cleaning to remove relatively large
dirt particles, such as debris or like solids, from the surface to
be cleaned, the nozzle assembly is lifted to a position over the
debris or like solids to cause them to be effectively sucked
through the suction channel, the nozzle assembly is apt to be
unnecessarily tilted downwards with the suction channel
consequently turning aside from above the debris or like solids,
making it difficult for the operator to place the nozzle assembly
over them.
In addition, although there will be no problem when and so long as
the paired brushes are adjusted to a small height position at which
the brushes protrude a small distance outwardly from the bottom of
the housing, the adjustment of the brushes to a great height
position at which they protrude a great distance outwardly from the
bottom of the housing poses a problem in that, since the nozzle
assembly itself is supported by the brushes above the surface to be
cleaned, the nozzle assembly during its movement along the surface
to be cleaned tends to lack stability and often undergoes a jolting
motion with the brushes buckling back and forth.
SUMMARY OF THE INVENTION
The present invention has been developed with a view to
substantially eliminating the above described disadvantages and
inconveniences inherent in the prior art nozzle assembly for a
household vacuum cleaner and has for its essential object to
provide an improved nozzle assembly wherein means for restraining
the nozzle assembly from undergoing an arbitrary tilting motion
relative to the tubular handle is utilized to increase the ease of
use.
Another important object of the present invention is to provide an
improved nozzle assembly of the type referred to above, wherein the
nozzle assembly can be locked relative to the tubular handle to
avoid the relative tilt when the nozzle assembly is desired to be
placed so as to be over debris or like solids in the course of
cleaning or when the brushes are so adjusted as to protrude a
maximum available distance outwards from the nozzle assembly, but
can be freely tiltable relative thereto during the other cleaning
conditions than those specified above.
A further object of the present invention is to provide an improved
nozzle assembly of the type referred to above, wherein a brush
height adjustment for adjusting the position of brushes, i.e., the
height of the brushes which protrude outwards from the nozzle
assembly, and the restraining means are so operatively associated
as to restrain the nozzle assembly from undergoing the arbitrary
tilt when the brushes are adjusted so as to protrude a maximum
available distance outwards from the nozzle assembly.
A still further object of the present invention is to provide an
improved nozzle assembly of the type referred to above, wherein the
restraining means is constituted by a brake shoe carried by the
brush height adjustment and an engagement surface of the transverse
barrel with which the brake shoe is engageable so that the nozzle
assembly can be locked at any desired position relative to the
tubular handle.
A still further object of the present invention is to provide an
improved nozzle assembly of the type referred to above, wherein the
restraining means comprises an engagement pin carried by the brush
height adjustment and normally biased so as to protrude in one
direction, which pin is engageable in a detent recess, defined in
the transverse barrel, when the detent recess is brought into
alignment with the pin as a result of the tilt of the nozzle
assembly relative to the tubular handle.
A yet further object of the present invention is to provide an
improved nozzle assembly of the type referred to above, wherein the
brush height adjustment can be carried out selectively to a
plurality of height positions to optimize the drag force according
to the condition of the surface to be cleaned.
A yet further object of the present invention is to provide an
improved nozzle assembly of the type referred to above, wherein the
brush height adjustment can be clicked to any one of the detent
positions corresponding to the brush height positions.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will
become clear from the following description taken in conjunction
with preferred embodiments thereof with reference to the
accompanying drawings, in which:
FIG. 1 is a perspective view of a suction nozzle assembly for a
household vacuum cleaner embodying the present invention;
FIG. 2 is a perspective view of the suction nozzle assembly as
viewed from below;
FIG. 3 is a top plan view of the suction nozzle assembly with a top
housing component removed;
FIG. 4 is a longitudinal sectional view of the suction nozzle
assembly;
FIG. 5 is an exploded view of an essential portion of the suction
nozzle assembly according to one embodiment of the present
invention;
FIGS. 6 to 8 are fragmentary transverse sectional views of the
nozzle assembly with brushes shown as adjusted to different
heights, respectively;
FIGS. 9 and 10 are views similar to FIG. 5, showing second and
third embodiments of the present invention, respectively;
FIG. 11 is a view similar to FIG. 5, showing a fourth embodiment of
the present invention;
FIGS. 12 and 13 are transverse sectional views of a portion of the
nozzle assembly, showing the brush height adjustment at different
operative positions, respectively; and
FIG. 14 is a view similar to FIGS. 12 and 13, showing a
modification of the embodiment of FIG. 11.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Before the description of the present invention proceeds, it is to
be noted that like parts are designated by like reference numerals
throughout the accompanying drawings.
Referring now to FIGS. 1 to 8, a generally T-shaped nozzle assembly
for a household vacuum cleaner comprises a generally rectangular
flattened box-like housing 1 including top and bottom housing
components 2 and 3 connected together one above the other by means
of a circumferential bumper 4. A suction spout of generally
T-shaped configuration including a transverse barrel 6 and a
coupling stem 5 protruding perpendicularly from an intermediate
portion of the transverse barrel 6 is connected to the housing 1
with the transverse barrel 6 rotatably received in an intermediate
portion of the housing 1 and with the coupling stem 23 protruding
rearwardly of the housing 1 generally at right angles thereto.
The bottom housing component 3 has a pair of spaced casters 7
rotatably carried thereby on respective sides of the transverse
barrel 6 and also has a suction channel 10 defined therein so as to
open at the bottom of the nozzle assembly. The suction channel 10
is constituted by a suction opening 8 and a pair of elongated
suction recesses 9 in line with each other and extending from the
suction opening 8 in the opposite directions with respect to each
other, respectively, lengthwise of the housing 1. A pair of
parallel slots 10' are defined in the bottom housing component 3 on
respective sides of the suction channel 10 so as to extend
lengthwise of the housing 1. As best shown in FIGS. 6 to 8, a lip
member 11 made of a strip of flexible material, for example,
rubber, is secured to the bottom housing component 3 with one of
its opposite sides embedded in a region of the bottom housing
component 3 between the suction channel 10 and one of the slots 10'
adjacent the transverse barrel 6 and extends lengthwise of the
housing 3 generally in parallel to the suction channel 10.
Within the interior of the housing 1, there is disposed a pair of
brushes 12 and a brush height adjusting body 13. The brushes 12 are
of identical construction with each other each comprising a
respective holder bar 14 having a plurality of equally spaced
bundles of bristles 15, which bundles 15 are implanted on the
respective holder bar 14. The holder bars 14 have formed at their
opposite ends bearing holes 16 and are movably supported by the
bottom housing component 3 with the bearing holes 16 receiving
respective bosses 17 therethrough, which bosses 17 are integrally
formed with the bottom housing component 3 so as to protrude
towards the top housing component 2 as best shown in FIG. 4. The
brushes 12 so supported in the manner as hereinabove described can
project outwards from the respective slots 10' to any one of a
plurality of, for example, maximum, intermediate and minimum,
height positions as will be described later.
The brush height adjusting body 13 is a generally rectangular
framework including a pair of parallel transverse strips 18 and a
pair of spaced bridge members bridging between the transverse
strips 18. This brush height adjusting body 13 is positioned within
the interior of the housing 1 for movement in a direction
lengthwise of the housing 1 and is movably supported by and
sandwiched between the top and bottom housing components 2 and 3.
This adjusting body 13 is operatively associated with the brushes
12 and, for this purpose, each of the transverse strips 18 has its
opposite end portions provided with stepped guide grooves 19 each
having three steps corresponding respectively to the maximum,
intermediate and minimum height positions for the brushes 12. On
the other hand, each of the holder bars 14 has a pair of spaced
pins 20 protruding laterally from the opposite end portions
thereof. The brushes 12 are operatively coupled with the adjusting
body 13 with the pins 20 inserted in the respective stepped guide
grooves 19, so that as the adjusting body 13 is adjustably moved in
a direction lengthwise of the housing 1, the brushes 12 are moved
in a direction perpendicular to the direction of movement of the
adjusting body 13. As best shown in FIG. 1 in combination with FIG.
5, the top housing component 2 has formed therein a rectangular
slot 22 through which a manipulatable knob member 21 rigidly
mounted on, or otherwise integrally formed with, one of the bridge
members of the adjusting body l3, protrudes loosely for access by
the operator. Thus, it will readily be seen that, by moving the
knob member 21 within the slot 22, the adjusting body 13 can be
moved in the direction parallel to the direction of movement of the
knob 21, i.e., lengthwise of the housing 1 for the adjustment of
the height of the brushes 12 that project outwards through the
respective slots 10'.
The coupling stem 5 of the suction spout is fluid-connected with a
tubular handle 26 through an elbow 23 having one end rotatably
coupled with the coupling stem 5 and the other end received in the
tubular handle 23. The transverse barrel 6 has a wall portion
provided with an opening 24' through which the suction channel 10
is communicated with the tubular handle 26 which is in turn
communicated with the vacuum source. One end of the transverse
barrel 6 has a flange 6a integral therewith and protruding axially
thereof, which flange 6a is provided with a generally V-shaped
recess 24 extending axially inwardly of the transverse barrel 6.
Operatively associated with the recess 24 is an engagement piece 25
integrally formed with, or otherwise rigidly mounted on, the
adjusting body 13. The engagement piece 25 on the adjusting body 13
is so shaped and so positioned that, only when the adjusting body
13 is moved rightwards, as viewed in FIG. 3, to the maximum height
position as shown by the double-dotted chain line, will the
engagement piece 25 be engaged in the recess 24 to prevent the
nozzle assembly as a whole from tilting relative to the tubular
handle 26 about the longitudinal axis of the transverse barrel
6.
The other of the bridge members remote from the maipulatable knob
member 21 is provided with a resilient tongue 28 protruding
therefrom in a direction away from the manipulatable knob member 21
and parallel to the longitudinal direction of the adjusting body
13, the free end of which tongue 27 is provided with an integral
detent piece 28 selectively engageable in any one of detent
recesses 29a, 29b and 29c formed in the top housing component 2 in
alignment with the path of movement of such detent piece 28. The
detent recesses 29a, 29b and 29c correspond in position
respectively to the maximum, intermediate and minimum height
positions of the adjusting body 13.
The the nozzle assembly constructed as hereinbefore described
operates in the following manner. As is usual with most
conventional nozzle assemblies, dirt sucked into the suction
channel 10 through the suction opening 8 and the suction recesses 9
on respective sides of the suction opening 8 during the operation
of the vacuum cleaner is further sucked into a dust bag (not shown)
through the suction spout, the elbow 23 and the tubular handle 26
which may be coupled with the canister either directly or through a
flexible hose (not shown).
Depending on the type of the surface to be cleaned, the height of
the brushes 12, that is, the distance which the brushes 15 project
outwards through the respective slots 10', has to be adjusted. This
will be described with particular reference to FIGS. 6 to 8.
In the case where the surface to be cleaned comprises a carpet as
shown in FIG. 8, the adjusting body 13 has to be moved to the
minimum height position by manipulating the knob member 21. As the
adjusting body 13 is moved towards the maximum height position, the
pins 20 on the respective brush holder bars 14 are moved within the
stepped guide grooves 19 to the highest step at which the brush
bristles 15 are retracted inwardly of the housing 1 through the
slots 10'. More specifically, upon the arrival of the adjusting
body 13 at the minimum height position, the bundled bristles 15 of
the front brush 12 with respect to the direction of forward
movement of the nozzle assembly during the cleaning are retracted
inwardly through the associated slot 10' into the housing 1 whereas
the bundled bristles 15 of the rear brush 12 protrude to a height
smaller than the height of the lip member 11 as shown in FIG.
8.
In the condition shown in FIG. 8, the lip member 11 slidingly
contacts the carpet, providing a curtain that permits dirt, located
frontwardly and laterally of the nozzle assembly, to be sucked up.
At this time, a maximum inlet velocity of air being sucked in can
be obtained, that is, the suction force is maximized. It is to be
noted that the bundled bristles 15 of the rear brush 12 serve to
drag dirt, clinging to the carpet, off the carpet, which dirt is
subsequently sucked into the suction channel 10 when the nozzle
assembly is drawn backwards.
When the surface to be cleaned comprises a flat floor, for example,
a bare floor such as shown in FIG. 7, and where the cleaning is
effected without substantially reducing the inlet velocity of air
being sucked in, the adjusting body 13 has to be moved to the
intermediate height position as shown in FIG. 7. At this time, the
pins 20 are moved within the guide grooves 19 to an intermediate
step between the highest and lowest steps, at which the bundles of
bristles 15 project outwardly of the housing 1 to an intermediate
height generally equal to the height of the lip member 11. Even in
this condition, the lip member 11 slidingly contacts the floor
surface and, therefore, a relatively high inlet velocity of air
being sucked in can be obtained.
It is to be noted that, when the adjusting body 13 is moved to
either the maximum height position or the intermediate height
position, the engagement piece 25 is disengaged from the recess 24
and, accordingly, the tubular handle 26 connected with the suction
spout is freely tiltable relative to the nozzle assembly to
accommodate changes in posture of the operator running the vacuum
cleaner. Thus, regardless of what posture the operator may take
during the cleaning of the surface to be cleaned, the nozzle
assembly can be kept substantially parallel to the surface being
cleaned to apply an efficient cleaning action to the surface.
When it happens that, during the cleaning of the floor, the force
required to push the nozzle assembly forwards, that is, the drag
force, is desired to be reduced by reducing the inlet velocity of
air being sucked in, the adjusting body 13 has to be moved to the
maximum height position as shown in FIG. 6. At this time, the pins
20 are guided within the guide grooves 19 to the lowest step at
which the bundles bristles 15 project outwards to the maximum
height. During the cleaning with the bundled bristles 15 projecting
to the maximum height as shown in FIG. 6, the lip member 11 is
lifted above the floor and, accordingly, air outside the nozzle
assembly is drawn from all directions into the suction channel 10
and the drag force with which the nozzle assembly is drawn towards
the floor is consequently reduced.
At the same time, the engagement piece 25 is engaged in the recess
24 so that the adjusting body 13 is held at the maximum height
position and, accordingly, the nozzle assembly is prevented from
undergoing any arbitrary tilting motion relative to the tubular
handle 26. As is well understood by those skilled in the art, when
and so long as the bundled bristles 15 protrude outwards from the
bottom of the nozzle assembly to the maximum height as shown in
FIG. 6, the nozzle assembly itself is substantially supported above
the floor by the brushes and is, therefore, apt to be jolted as it
is moved forwards and backwards with the bristles 15 buckling
resiliently. Specifically, as the nozzle assembly is moved forwards
by the application of an external pushing force to the tubular
handle 26 during the cleaning, the bundled bristles 15 of the rear
brush 12 are bent rearwardly with the front of the nozzle assembly
consequently pitched upwards. Conversely, when the nozzle assembly
is moved backwards by the application of an external pulling force
to the tubular handle 26, the bundled bristles 15 of the rear brush
12 return to the original shape to make the nozzle assembly assume
a generally parallel relationship to the floor.
In view of the above, the engagement of the engagement piece 25
fast or integral with the adjusting body 13 into the recess 24 to
restrain the nozzle assembly from tilting relative to the tubular
handle 26 is advantageous in that any arbitrary pitching motion of
the nozzle assembly as a result of the buckling of the bundled
bristles 15 can be avoided and also in that, where debris or like
solids are desired to be removed, the nozzle assembly can be placed
so as to hang over them without changing the angular relationship
between the nozzle assembly and the tubular handle 26.
The restraining mechanism for restraining the nozzle assembly from
tilting relative to the tubular handle, which has been shown as
comprised of the engagement piece 25 in combination with the recess
24 in the foregoing embodiment, may take numerous forms such as
shown in FIGS. 9 and 10.
Referring to FIG. 9, the restraining mechanism comprises a brake
shoe 25a rigidly mounted on the adjusting body 13 for movement
together therewith, which shoe 25a is engageable with an arcuate
end face 24a of the flange 6a integral with the transverse barrel
6. It will readily be seen that, when the adjusting body 13 is
moved to the maximum height position, the brake shoe 25a is brought
into engagement with the arcuate end face 24a of the flange 6a.
The restraining mechanism of the construction shown in and
described with reference to FIG. 9 is particularly advantageous in
that the nozzle assembly can be restrained at any desired angular
position relative to the tubular handle 26.
Referring now to FIG. 10, the restraining mechanism shown therein
comprises an engagement pin 31 carried by the adjusting body 13 and
movable between retracted and projected positions, and a biasing
spring 30 urging the engagement pin 30 in one direction to the
projected position. When the adjusting body 13 is moved to the
maximum height position, the engagement pin 31 normally biased by
the spring 30 is moved into a blind hole 32, defined in the flange
6a so as to extend axially inwardly from the arcuate end face of
such flange 6a, thereby to restrain the nozzle assembly from
tilting relative to the tubular handle 26.
This restraining mechanism shown in and described with reference to
FIG. 10 is advantageous in that, since the tip of the engagement
pin 31 slidingly rests on the arcuate end face of the flange 6a
when the adjusting body 13 is moved to the maximum height position
without the angular relationship between the nozzle assembly and
the tubular handle 26 being fixed beforehand, no complicated
alignment procedure is required.
During the adjustment of the adjusting body 13 to any one of the
maximum, intermediate and minimum height positions, the detent
piece 28 of the resilient tongue 27 is engaged in a corresponding
one of the detent recesses 29a, 29b and 29c defined interiorly in
the top housing component 2. However, it may happen that, when it
is desired to move the adjusting body 13, for example, from the
maximum height position towards the intermediate height position
and, hence, the detent piece 28 which has been engaged in the
rightmost detent recesses 29a as viewed in FIG. 4 is to be engaged
in the intermediate detent recess 29b next to the rightmost detent
recess 29a, the detent piece 28 skips over the intermediate detent
recess 29b. This is particularly true when an excessive pushing or
pulling force is applied to the manipulatable knob member 21.
The above discussed problem can, according to the present
invention, be advantageously eliminated by the provision of a
failsafe device. Referring now to FIGS. 11 to 13, the failsafe
device comprises a second resilient tongue 27a integrally formed
with the bridge member of the adjusting body 13 so as to extend
next to and parallel to the first resilient tongue 27, the free end
of which tongue 27a has an integrally formed detent piece 28a. The
second resilient tongue 27a having the detent piece 28a may be of
identical construction with the first resilient tongue 27 having
the detent piece 28.
Cooperable with the second resilient tongue 27a and forming another
part of the failsafe device is a cam piece 33 of generally
triangular configuration. A base portion of said cam piece 33 which
corresponds to the base of the shape of a triangle is formed
integrally with, or otherwise secured rigidly to, the top housing
component 2 in alignment with the path of movement of the detect
piece 28a. The cam piece 33 has its apex portion recessed inwardly
to define a detent recess 29d, said detent recess 29 being so
positioned that simultaneous with the engagement of the detent
piece 28 into the intermediate detent recess 29b, the detent piece
28a can be engaged in the detent recess 29d.
The failsafe device of the construction shown in and described with
reference to FIGS. 10 to 13 operates in the following manner.
Assuming that the adjusting body 13 is moved from the maximum
height position towards the intermediate height position, the
detent piece 28a integral with the second resilient tongue 27a
relatively slides over the cam piece 33 with the second tongue 27a
consequently forced to bend downwards against the resiliency of
such tongue 27a. As the second tongue 27a is so deformed, the
resilient tongue 27a accumulates energy necessary to restore it to
the original shape. Accordingly, by the action of the accumulated
energy, the detent piece 28a can be instantly engaged in the detent
recess 29d in the cam piece 33 an the second resilient tongue 27a
restored to its original shape immediately upon the arrival of the
adjusting body 13 at the intermediate height position as shown by
the imaginary lines in FIGS. 12 and 13.
It is to be noted that the foregoing description concerning the
operation of the failsafe device equally applies even where the
adjusting body 13 is moved from the minimum height position towards
the intermediate height position.
In the modification shown in FIG. 14, the failsafe device comprises
a generally arcuate leaf spring member 34 having one end secured to
the bottom housing component 3. This leaf spring member 34 is so
positioned and so shaped that, as the detent piece 28 is ready to
be engaged in the intermediate detent recess 29b, the resilient
tongue 27 then deformed downwardly depresses the leaf spring member
34 against the resiliency of the leaf spring member 34 to cause the
latter to accumulate energy necessary to restore it to the original
shape. Thus, by the action of the accumulated energy, the detent
piece 28 ready to be engaged in the intermediate detent recess 29b
can be instantaneously urged to fall into the intermediate detent
recess 29b.
With the use of the failsafe device of the construction shown in
any one of FIGS. 10 to 13 and FIG. 14, the possibility of the
detent piece 28 integral with the resilient tongue 27 skipping over
the intermediate detent recess 29b can be advantageously
avoided.
From the foregoing description, it has now become clear that the
suction nozzle assembly embodying the present invention comprises a
suction spout having a coupling stem for fluid-connection with a
vacuum cleaner, a generally rectangular nozzle housing tiltably
connected with the suction spout and having a sweeping surface
defined at the bottom thereof, said sweeping surface being adapted
to confront a surface to be cleaned, an elongated brush assembly
carried by the nozzle housing for movement between projected and
retracted positions in a direction perpendicular to the
longitudinal direction of the housing through the sweeping surface,
a brush height adjustment for adjustably moving the brush assembly
to either the projected or the retracted positions, and a
restraining mechanism for restraining the housing from undergoing
an arbitrary tilting motion relative to the suction spout.
Accordingly, it is also clear that during the normal cleaning of
the surface to be cleaned, the nozzle assembly can be kept
generally parallel to the surface to be cleaned regardless of the
position of the tubular handle connected to the suction spout, and
regardless of the posture of the operator running the vacuum
cleaner.
Where drag force is desired to be reduced by causing the brush
assembly to protrude a maximum available distance outwards from the
sweeping surface, or when relatively large dirt particles such as
debris or like solids are desired to be sucked up, the nozzle
assembly can be restrained from undergoing any arbitrary tilting
motion relative to the tubular handle and can therefore be
stabilized.
Although the present invention has fully been described in
connection with the preferred embodiments thereof with reference to
the accompanying drawings, it is to be noted that various changes
and modifications will be apparent to those skilled in the art.
Such changes and modifications are to be understood as included
within the scope of the present invention as defined by the
appended claims unless they depart therefrom.
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